1. Field of the Invention
The present invention relates to a method and system for providing information, such as image, video and/or audio data, to remote clients. More particularly, the invention relates to a method and system for detecting an event, recording visual and/or audio information associated with the event, alerting a remote client of the event, and transmitting the visual and/or audio information to a remote client device (e.g., PC, PDA or cellular telephone).
2. Description of the Related Technology
Analog Closed Circuit Television (CCTV) systems have been used for remote presence and security viewing for almost fifty years. By utilizing shielded coaxial cable as the medium to transmit the video from an analog camera to a central location for viewing on a television monitor, these networks are secure from unauthorized clients gaining access to the video. The cost of installing the shielded coaxial cable, however, prohibits the wide area transmission of this video. Generally, a central viewing room is located on the premises where the cameras are installed. The video can be viewed off the premises or archived by transferring the video taken for each camera to a videotape via a videocassette recorder (VCR). This mode of transmission and storage of video is inefficient, as it requires a large amount of human intervention. Also, since CCTV systems are closed to anyone outside of the central viewing room, off site monitoring of the video is not possible. Controlling which clients are allowed access to the central viewing room is the only way to control access to the video from any camera.
With the advent of the Internet, networked digital video cameras are now available. These digital video cameras transmit their captured video using Internet Protocol (IP) technologies. Clients authorized to access the digital communications network (e.g., Local Area Network (LAN), Wide Area Network (WAN), World Wide Web (“www” or “Internet”), to which the cameras are communicatively linked, can view the video from a particular camera from their Personal Computer (PC). Access to the video is controlled utilizing technologies developed for the Internet. A client, utilizing a web browser on their personal computer, can access the video captured by a particular camera by accessing that camera via a web page or directly accessing the camera if is “web-server enabled.” Web-server enabled cameras are assigned their own unique URL address and contain the necessary circuitry and embedded software so that clients can directly access their video feed via the Internet. Such cameras are well known in the art. Similarly, techniques for accessing the video feed of a camera via a designated web page or portal are also well known in the art. Typically, in order to access these cameras or web portals, a client is authenticated through a client username and password that is unique to that client. The system can be compromised if an unauthorized user learns the username and password of an authorized client.
Digital communication networks also allow video captured by digital and/or analog cameras to be made accessible to clients not physically located on the premises where the video is captured. This ability to transmit the video via digital communication networks has greatly improved the efficiency for archiving and viewing the captured video by offsite clients. However, such systems are vulnerable to attack. For example, Internet hackers can steal usernames and passwords and gain access to the content being transmitted by these cameras. This is a major problem that has forced many corporations and personal clients to employ encryption technologies that increase the cost of the service.
In an attempt to conserve the bandwidth required to transmit video over an IP network, digital cameras have utilized data compression techniques. Generally, through known video compression techniques, the size of the video data to be transmitted over the network can be reduced by a factor of 100 to 140 times the size of the original video data. This greatly reduces the cost and bandwidth requirements of transmitting the video. In order for a client to view the video on their personal computer (PC), the client must have the corresponding decompression software available to them. Since the approach used by most camera companies is proprietary, this software must be loaded onto the PC prior to the client accessing the data from a camera. If a client has cameras on their network that are manufactured by different sources, these cameras will require their own stand-alone decompression software. This adds to the complexity in trying to use the system, since clients must know which compression/decompression software is required for each camera. Also, it is not currently possible for a client to access remote cameras using a device other than a PC. New devices such as “Smart Cell Phones,” however, have the capability to view images and video as long as the data compression and transmission conforms to known standards adopted for such phones. However, cellular phones do not currently provide clients with the ability to access remote cameras customized specifically for their viewing.
Additionally, it would be desirable to alert or notify remote clients of the occurrence of a pre-specified event or phenomenon and thereafter provide live, real-time (or as close as the transmission speed will allow) visual and/or audio data to the remote clients who are registered or authorized to receive such alerts and corresponding data. Currently, neither cell phones, nor any other type of remote client devices (e.g., PC's, PDA's) for that matter, provide this functionality to clients.
Today's digital cameras have greatly reduced the cost of installation. Since these cameras can utilize the IP data format to transmit the video, they can be placed anywhere there is an Ethernet jack for connection to a digital communications network (e.g., LAN, WAN or Internet). Analog cameras require a shielded coaxial cable to be installed for each camera. However, with the use of appropriate analog-to-digital (A/D) converters and processing circuitry to format, compress, and transmit data across a digital communications network, analog cameras can also be placed at remote locations and accessed via a digital communications network. This flexibility of being able to place cameras at various designated remote locations and connect the cameras to a network, potentially allows clients to obtain visual information in accordance with various scenarios or objectives. One particular scenario or objective could be the placing of a camera to monitor who enters a particular door over a week-long period. Another example is the placing of a camera to record how many cars park in a certain location during a 12-hour period. This flexibility also presents a problem, however, since digital cameras can potentially be placed in areas that infringe upon the privacy rights of individuals or for other illegal purposes. Without the knowledge of the network administrator, a client with the intent of spying on individuals or private locations could move or place cameras at improper locations.